The phrase "weak immunity" is correct and usable in written English.
You can use it to refer to a person's lowered ability to fight off diseases or infections due to a weakened immune system. For example, "People with weak immunity are susceptible to even the mildest of illnesses."
Live vaccines contain weakened forms of the virus, but these vaccines can be dangerous when given to people with weak immunity.
Live vaccines can be dangerous when given to people with a weak immunity (who are described as immunocompromised), because in these people, the weakened virus can cause the original disease.
Neonatal mortality peaks are common in primates and may be caused by birth complications, congenital defects, poor mothering, or the weak immunity of newborns [15], [29].
One explanation for these findings may be that almost all people lacked or had only weak immunity against the pdmH1N1 virus at the start of the 2009 outbreak, as well as the pdmH1N1 virus being more contagious than seasonal influenza viruses (although it has lower pathogenicity) [25].
Thus, S. Typhi may induce only weak immunity, including a muted antibody response.
In addition, severely malnourished children are vulnerable to infections as a result of weak immunity and could be at risk in crowded hospital wards.
However, vaccination against tumors generally elicits a weaker immunity than vaccination against infectious diseases [ 41].
The same explanation can be given that the ABC transporter genes were down-regulated in the initial acute phase but up-regulated 4 weeks later due to a slower and less efficient host response caused by young age and weaker immunity.
Thus, the number of cases is higher in age/sex groups that have weaker immunities, more clinical infections and/or higher levels of exposure.
Certain challenging pathogens and weak immune responder subjects may require further optimization of the adjuvant formulation to maximize the magnitude and duration of the protective immunity.
Consistent with the results in previous studies reporting weak protective immunity to M2, vaccination with M2 VLPs in the absence of adjuvant did not prevent body weight losses in protected mice.
